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I have an OpenLayers client displaying tracks from a vector source. I would like to display an elevation profile of the track. When hovering mouse on a point on the elevation profile, a marker should appear on the corresponding map point. Are there any online resources on building this?

Tutorial for a similar control in Google Maps API

Example of page using the control

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It would be helpful to know what type of elevation profile you are using to achieve this but in reality it doesn't matter.

I managed to do this by assigning a function to a hover event on a Kendo chart but it could be done using a data table or similar. I'm assuming that you are using Openlayers 3?

Basically on hover, if you identify the latitude and longitude of the item; you will need to convert these values to a coordinate which matches the map's projection and then create a feature with these coordinates and it to the map.

It can only be added to the map by creating a vector source and adding this feature to the source, then creating a layer which uses this source, and adding this layer to the map.

I'll supply the code I used and hopefully you should be able to figure it out from there.

{
        // if a previous version of the layer was added, remove it
        if (session.map.elevationMarkerLayer) {
            session.map.removeLayer(session.map.elevationMarkerLayer);
        }

        var LonLat = [];
        LonLat.push(e.dataItem.Longitude, e.dataItem.Latitude);
        var coords = ol.proj.transform(LonLat, 'EPSG:4326', 'EPSG:3857');

        // set a style for the icon
        var iconStyle = new ol.style.Style({
            image: new ol.style.RegularShape({
                fill: new ol.style.Fill({
                    color: '#F58026'
                }),
                stroke: new ol.style.Stroke({
                    color: '#000',
                    width: 2
                }),
                points: 3,
                radius: 15,
                rotation: 0,//Math.PI / 4,
                angle: 0
            }),
            text: new ol.style.Text({
                text: e.value.toString(),
                scale: 1.3,
                offsetX: 0,
                offsetY: 15,
                fill: new ol.style.Fill({
                    color: '#F58026'
                }),
                stroke: new ol.style.Stroke({
                    color: '#000',
                    width: 4
                })
            })
        });
        var elevationMarker = new ol.Feature({
            type: 'elevationMarker',
            geometry: new ol.geom.Point(coords)
        });
        session.map.elevationMarkerLayer = new ol.layer.Vector({
            source: new ol.source.Vector({
                features: [elevationMarker]
            }),
            style: iconStyle,
            zIndex: 30
        });
        session.map.addLayer(session.map.elevationMarkerLayer);
        // timeout method to make this temporary
        setInterval(function () {
            session.map.removeLayer(session.map.elevationMarkerLayer);
        }, 10000);
    }

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